// Copyright 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "content/shell/browser/shell_url_request_context_getter.h"

#include <memory>
#include <utility>

#include "base/command_line.h"
#include "base/logging.h"
#include "base/memory/ptr_util.h"
#include "base/single_thread_task_runner.h"
#include "base/strings/string_number_conversions.h"
#include "base/strings/string_split.h"
#include "base/strings/string_util.h"
#include "base/threading/sequenced_worker_pool.h"
#include "base/threading/worker_pool.h"
#include "build/build_config.h"
#include "content/public/browser/browser_thread.h"
#include "content/public/browser/cookie_store_factory.h"
#include "content/public/common/content_switches.h"
#include "content/shell/browser/shell_network_delegate.h"
#include "content/shell/common/shell_content_client.h"
#include "content/shell/common/shell_switches.h"
#include "net/base/cache_type.h"
#include "net/cert/cert_verifier.h"
#include "net/cert/ct_policy_enforcer.h"
#include "net/cert/multi_log_ct_verifier.h"
#include "net/cookies/cookie_monster.h"
#include "net/dns/host_resolver.h"
#include "net/dns/mapped_host_resolver.h"
#include "net/http/http_auth_handler_factory.h"
#include "net/http/http_cache.h"
#include "net/http/http_network_session.h"
#include "net/http/http_server_properties_impl.h"
#include "net/http/transport_security_state.h"
#include "net/net_features.h"
#include "net/proxy/proxy_service.h"
#include "net/ssl/channel_id_service.h"
#include "net/ssl/default_channel_id_store.h"
#include "net/ssl/ssl_config_service_defaults.h"
#include "net/url_request/data_protocol_handler.h"
#include "net/url_request/file_protocol_handler.h"
#include "net/url_request/static_http_user_agent_settings.h"
#include "net/url_request/url_request_context.h"
#include "net/url_request/url_request_context_storage.h"
#include "net/url_request/url_request_intercepting_job_factory.h"
#include "net/url_request/url_request_job_factory_impl.h"
#include "url/url_constants.h"

namespace content {

namespace {

    void InstallProtocolHandlers(net::URLRequestJobFactoryImpl* job_factory,
        ProtocolHandlerMap* protocol_handlers)
    {
        for (ProtocolHandlerMap::iterator it = protocol_handlers->begin();
             it != protocol_handlers->end();
             ++it) {
            bool set_protocol = job_factory->SetProtocolHandler(
                it->first, base::WrapUnique(it->second.release()));
            DCHECK(set_protocol);
        }
        protocol_handlers->clear();
    }

} // namespace

ShellURLRequestContextGetter::ShellURLRequestContextGetter(
    bool ignore_certificate_errors,
    const base::FilePath& base_path,
    scoped_refptr<base::SingleThreadTaskRunner> io_task_runner,
    scoped_refptr<base::SingleThreadTaskRunner> file_task_runner,
    ProtocolHandlerMap* protocol_handlers,
    URLRequestInterceptorScopedVector request_interceptors,
    net::NetLog* net_log)
    : ignore_certificate_errors_(ignore_certificate_errors)
    , base_path_(base_path)
    , io_task_runner_(std::move(io_task_runner))
    , file_task_runner_(std::move(file_task_runner))
    , net_log_(net_log)
    , request_interceptors_(std::move(request_interceptors))
{
    // Must first be created on the UI thread.
    DCHECK_CURRENTLY_ON(BrowserThread::UI);

    std::swap(protocol_handlers_, *protocol_handlers);

    // We must create the proxy config service on the UI loop on Linux because it
    // must synchronously run on the glib message loop. This will be passed to
    // the URLRequestContextStorage on the IO thread in GetURLRequestContext().
    proxy_config_service_ = GetProxyConfigService();
}

ShellURLRequestContextGetter::~ShellURLRequestContextGetter()
{
}

std::unique_ptr<net::NetworkDelegate>
ShellURLRequestContextGetter::CreateNetworkDelegate()
{
    return base::WrapUnique(new ShellNetworkDelegate);
}

std::unique_ptr<net::ProxyConfigService>
ShellURLRequestContextGetter::GetProxyConfigService()
{
    return net::ProxyService::CreateSystemProxyConfigService(io_task_runner_,
        file_task_runner_);
}

std::unique_ptr<net::ProxyService>
ShellURLRequestContextGetter::GetProxyService()
{
    // TODO(jam): use v8 if possible, look at chrome code.
    return net::ProxyService::CreateUsingSystemProxyResolver(
        std::move(proxy_config_service_), 0, url_request_context_->net_log());
}

net::URLRequestContext* ShellURLRequestContextGetter::GetURLRequestContext()
{
    DCHECK_CURRENTLY_ON(BrowserThread::IO);

    if (!url_request_context_) {
        const base::CommandLine& command_line = *base::CommandLine::ForCurrentProcess();

        url_request_context_.reset(new net::URLRequestContext());
        url_request_context_->set_net_log(net_log_);
        network_delegate_ = CreateNetworkDelegate();
        url_request_context_->set_network_delegate(network_delegate_.get());
        storage_.reset(
            new net::URLRequestContextStorage(url_request_context_.get()));
        storage_->set_cookie_store(CreateCookieStore(CookieStoreConfig()));
        storage_->set_channel_id_service(base::WrapUnique(
            new net::ChannelIDService(new net::DefaultChannelIDStore(NULL),
                base::WorkerPool::GetTaskRunner(true))));
        storage_->set_http_user_agent_settings(
            base::MakeUnique<net::StaticHttpUserAgentSettings>(
                "en-us,en", GetShellUserAgent()));

        std::unique_ptr<net::HostResolver> host_resolver(
            net::HostResolver::CreateDefaultResolver(
                url_request_context_->net_log()));

        storage_->set_cert_verifier(net::CertVerifier::CreateDefault());
        storage_->set_transport_security_state(
            base::WrapUnique(new net::TransportSecurityState));
        storage_->set_cert_transparency_verifier(
            base::WrapUnique(new net::MultiLogCTVerifier));
        storage_->set_ct_policy_enforcer(
            base::WrapUnique(new net::CTPolicyEnforcer));
        storage_->set_proxy_service(GetProxyService());
        storage_->set_ssl_config_service(new net::SSLConfigServiceDefaults);
        storage_->set_http_auth_handler_factory(
            net::HttpAuthHandlerFactory::CreateDefault(host_resolver.get()));
        storage_->set_http_server_properties(
            base::MakeUnique<net::HttpServerPropertiesImpl>());

        base::FilePath cache_path = base_path_.Append(FILE_PATH_LITERAL("Cache"));
        std::unique_ptr<net::HttpCache::DefaultBackend> main_backend(
            new net::HttpCache::DefaultBackend(
                net::DISK_CACHE,
#if defined(OS_ANDROID)
                // TODO(rdsmith): Remove when default backend for Android is
                // changed to simple cache.
                net::CACHE_BACKEND_SIMPLE,
#else
                net::CACHE_BACKEND_DEFAULT,
#endif
                cache_path, 0,
                BrowserThread::GetTaskRunnerForThread(BrowserThread::CACHE)));

        net::HttpNetworkSession::Params network_session_params;
        network_session_params.cert_verifier = url_request_context_->cert_verifier();
        network_session_params.transport_security_state = url_request_context_->transport_security_state();
        network_session_params.cert_transparency_verifier = url_request_context_->cert_transparency_verifier();
        network_session_params.ct_policy_enforcer = url_request_context_->ct_policy_enforcer();
        network_session_params.channel_id_service = url_request_context_->channel_id_service();
        network_session_params.proxy_service = url_request_context_->proxy_service();
        network_session_params.ssl_config_service = url_request_context_->ssl_config_service();
        network_session_params.http_auth_handler_factory = url_request_context_->http_auth_handler_factory();
        network_session_params.http_server_properties = url_request_context_->http_server_properties();
        network_session_params.net_log = url_request_context_->net_log();
        network_session_params.ignore_certificate_errors = ignore_certificate_errors_;
        if (command_line.HasSwitch(switches::kTestingFixedHttpPort)) {
            int value;
            base::StringToInt(command_line.GetSwitchValueASCII(
                                  switches::kTestingFixedHttpPort),
                &value);
            network_session_params.testing_fixed_http_port = value;
        }
        if (command_line.HasSwitch(switches::kTestingFixedHttpsPort)) {
            int value;
            base::StringToInt(command_line.GetSwitchValueASCII(
                                  switches::kTestingFixedHttpsPort),
                &value);
            network_session_params.testing_fixed_https_port = value;
        }
        if (command_line.HasSwitch(switches::kHostResolverRules)) {
            std::unique_ptr<net::MappedHostResolver> mapped_host_resolver(
                new net::MappedHostResolver(std::move(host_resolver)));
            mapped_host_resolver->SetRulesFromString(
                command_line.GetSwitchValueASCII(switches::kHostResolverRules));
            host_resolver = std::move(mapped_host_resolver);
        }

        // Give |storage_| ownership at the end in case it's |mapped_host_resolver|.
        storage_->set_host_resolver(std::move(host_resolver));
        network_session_params.host_resolver = url_request_context_->host_resolver();

        storage_->set_http_network_session(
            base::MakeUnique<net::HttpNetworkSession>(network_session_params));
        storage_->set_http_transaction_factory(base::MakeUnique<net::HttpCache>(
            storage_->http_network_session(), std::move(main_backend),
            true /* set_up_quic_server_info */));

        std::unique_ptr<net::URLRequestJobFactoryImpl> job_factory(
            new net::URLRequestJobFactoryImpl());
        // Keep ProtocolHandlers added in sync with
        // ShellContentBrowserClient::IsHandledURL().
        InstallProtocolHandlers(job_factory.get(), &protocol_handlers_);
        bool set_protocol = job_factory->SetProtocolHandler(
            url::kDataScheme, base::WrapUnique(new net::DataProtocolHandler));
        DCHECK(set_protocol);
#if !BUILDFLAG(DISABLE_FILE_SUPPORT)
        set_protocol = job_factory->SetProtocolHandler(
            url::kFileScheme,
            base::MakeUnique<net::FileProtocolHandler>(
                BrowserThread::GetBlockingPool()->GetTaskRunnerWithShutdownBehavior(
                    base::SequencedWorkerPool::SKIP_ON_SHUTDOWN)));
        DCHECK(set_protocol);
#endif

        // Set up interceptors in the reverse order.
        std::unique_ptr<net::URLRequestJobFactory> top_job_factory = std::move(job_factory);
        for (auto i = request_interceptors_.rbegin();
             i != request_interceptors_.rend(); ++i) {
            top_job_factory.reset(new net::URLRequestInterceptingJobFactory(
                std::move(top_job_factory), std::move(*i)));
        }
        request_interceptors_.clear();

        storage_->set_job_factory(std::move(top_job_factory));
    }

    return url_request_context_.get();
}

scoped_refptr<base::SingleThreadTaskRunner>
ShellURLRequestContextGetter::GetNetworkTaskRunner() const
{
    return BrowserThread::GetTaskRunnerForThread(BrowserThread::IO);
}

net::HostResolver* ShellURLRequestContextGetter::host_resolver()
{
    return url_request_context_->host_resolver();
}

} // namespace content
